Inequalities in mammography and Papanicolaou test coverage: a time-series study

ABSTRACT BACKGROUND: Cancer is a serious public issue problem worldwide. In Brazil, breast cancer is the most common type and cervical cancer is the third most frequent among women. OBJECTIVE: To analyze the temporal trend of coverage of mammography and cervical oncotic cytological testing, between 2007 and 2018. DESIGN AND SETTING: Time-series study conducted in the 26 Brazilian state capitals and in the Federal District. METHODS: A linear regression model was used to estimate trends in coverage of mammography and cervical oncotic cytological testing over the period. The data collection system for Surveillance of Risk and Protection Factors for Chronic Diseases by Telephone Survey (Vigitel) was used. RESULTS: A significant increase in mammography coverage was observed, from 71.1% in 2007 to 78.0% in 2018. There was a trend towards an increase among women with 0 to 8 years of schooling, in all regions of Brazil. Regarding cervical oncotic cytological testing coverage, there was a trend towards stability during the period analyzed, reaching 81.7% in 2018. On the other hand, there was a significant increase in the northern region. CONCLUSIONS: There was an improvement in the coverage of these screening examinations, especially regarding mammography. However, it is still necessary to expand their provision, quality and surveillance, aimed towards women's health.

To promote development and implementation of effective, integrated, sustainable and evidence-based public policies, the federal government launched the Strategic Action Plan for Confronting Chronic Noncommunicable Diseases in Brazil, 2011-2022. Among the proposed national targets were increases in mammography coverage among women between 50 and 69 years old to 70% and in Papanicolaou test coverage among women from 25 to 64 years old to 85%; promotion of improved quality of screening tests; and treatment of 100% of women diagnosed with precursor cancer lesions. Among the actions to speed up the diagnosis, there were investments in diagnostic capacity and infrastructure, especially in the northern and northeastern regions of Brazil. 6,7 OBJECTIVE Thus, the objective of the present study was to analyze the temporal trends of mammography and cervical oncotic cytological test coverage, between the years 2007 and 2018.

Study design and data collection
This study analyzed the trends in coverage of mammography and cervical oncotic cytological tests using data covering the years people answer the survey questions and, over the years in which Vigitel has been conducted, 382,255 adult women have been interviewed. Survey professionals have applied some adjustment procedures that have taken sex, age and education levels into account, with the aim of reducing the non-representation bias inherent to telephone interviews and seeking to make the sample distribution similar to the sociodemographic characteristics of the adult population of each state capital. 8 Details on the sampling and data collection process can be found in the published Vigitel results. 8,9 Indicator definition The mammography and cervical oncotic cytological testing coverage indicators used in the study were obtained through the following Vigitel questions: 8 • Percentage of women (50 to 69 years old) who underwent mammography examinations over the last two years: a measurement of the number of women between 50 and 69 years old who underwent mammography over the last two years, derived from the number of women between these ages who were interviewed. This was in answer to the questions: "Did you ever have a mammogram breast x-ray?" and "How long ago did you have a mammogram?". These questions were only applied to women between 50 and 69 years of age because this is the age range within which breast cancer screening through mammography is recommended.

RESULTS
Over the entire time period of the present study, there was an increase in mammography coverage performed within the last two years from 71.1% in 2007 to 78% in 2018. This represented a growth rate of 0.741 per year (P < 0.001). Stratified according to the number of years of schooling, there was a linear trend of progression among women with 0 to 8 years of schooling, from 66.1% to 73.5% (P < 0.001), while the coverage among the other schooling-level ranges remained static. There was a tendency towards significant increases in coverage for all age groups, from 73.4% to 78.6% among women aged 50 to 59 years and from 67.2% to 76.9% for those aged 60 to 69 years.
In all regions of Brazil, the trend was upward, and the northern region had the fastest growth rate (β = 1.613) among all the regions ( Table 1)     to 69 age group, which could explain the high number of women undergoing mammography under 50 years of age. 11 On the other hand, the Swiss Medical Council does not recommend any mammographic screening program in any age group because it considers that the benefit is small and questionable. 4 It is also noteworthy that the most recent evidence does not recommend breast self-examination, since its effectiveness has not been proven and health risks associated with this practice have been demonstrated. 1 Analysis on data from the Global Burden of Disease study indicated that mortality remained stable from 1990 to 2015 in Brazil and its states. There was no significant increase in any of the states in the northern and northeastern regions. 12 The increase in mammography coverage may explain the stability in mortality rates, but attention needs to be drawn to the worse performance in the northern and northeastern regions.
Coverage was also lower in these regions and this resulted from uneven geographical distribution of mammography devices and the lower operational capacity in these locations.
Healthcare inequalities generate different exposures to factors that determine health, illness and death. 13 It is important to advance The samples need to be satisfactory and, for the coverage to be considered adequate, the initial screening must take place with two negative examinations with a one-year interval between them, so that it becomes possible to move on to examinations every three years. These data regarding the sample and two negative results with a one-year interval were not addressed in the Vigitel questions during the telephone interview because of the specificity of the desired responses. In Brazil, obtaining access to the information needed for cervical cancer screening to be considered ideal is a challenge, given that there are no adequate surveillance mechanisms and no monitoring of the coverage of these tests. Papanicolaou examinations in Brazil are conducted in an opportunistic manner, and not through an organized scheme of surveillance and monitoring.

CONCLUSION
There was a trend of increasing mammography coverage among women aged 50 to 69 years and a static trend regarding cervical oncotic cytological testing among women aged 25 to 64 years living in Brazilian state capitals and the Federal District. However, differences in prevalence were observed, such that it was higher among better educated women and among women living in the southern and southeastern regions. Therefore, there is still a need to expand the provision, quality and availability of actions and services aimed at improving women's health and, above all, to prioritize investments in the regions that had the least coverage of these tests.